1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3   cx231xx-i2c.c - driver for Conexant Cx23100/101/102 USB video capture devices
4
5   Copyright (C) 2008 <srinivasa.deevi at conexant dot com>
6		Based on em28xx driver
7		Based on Cx23885 driver
8
9 */
10
11#include "cx231xx.h"
12#include <linux/module.h>
13#include <linux/kernel.h>
14#include <linux/i2c.h>
15#include <linux/i2c-mux.h>
16#include <media/v4l2-common.h>
17#include <media/tuner.h>
18
19
20/* ----------------------------------------------------------- */
21
22static unsigned int i2c_scan;
23module_param(i2c_scan, int, 0444);
24MODULE_PARM_DESC(i2c_scan, "scan i2c bus at insmod time");
25
26static unsigned int i2c_debug;
27module_param(i2c_debug, int, 0644);
28MODULE_PARM_DESC(i2c_debug, "enable debug messages [i2c]");
29
30#define dprintk1(lvl, fmt, args...)			\
31do {							\
32	if (i2c_debug >= lvl) {				\
33		printk(fmt, ##args);			\
34		}					\
35} while (0)
36
37#define dprintk2(lvl, fmt, args...)			\
38do {							\
39	if (i2c_debug >= lvl) {				\
40		printk(KERN_DEBUG "%s at %s: " fmt,	\
41		       dev->name, __func__ , ##args);	\
42      }							\
43} while (0)
44
45static inline int get_real_i2c_port(struct cx231xx *dev, int bus_nr)
46{
47	if (bus_nr == 1)
48		return dev->port_3_switch_enabled ? I2C_1_MUX_3 : I2C_1_MUX_1;
49	return bus_nr;
50}
51
52static inline bool is_tuner(struct cx231xx *dev, struct cx231xx_i2c *bus,
53			const struct i2c_msg *msg, int tuner_type)
54{
55	int i2c_port = get_real_i2c_port(dev, bus->nr);
56
57	if (i2c_port != dev->board.tuner_i2c_master)
58		return false;
59
60	if (msg->addr != dev->board.tuner_addr)
61		return false;
62
63	if (dev->tuner_type != tuner_type)
64		return false;
65
66	return true;
67}
68
69/*
70 * cx231xx_i2c_send_bytes()
71 */
72static int cx231xx_i2c_send_bytes(struct i2c_adapter *i2c_adap,
73				  const struct i2c_msg *msg)
74{
75	struct cx231xx_i2c *bus = i2c_adap->algo_data;
76	struct cx231xx *dev = bus->dev;
77	struct cx231xx_i2c_xfer_data req_data;
78	int status = 0;
79	u16 size = 0;
80	u8 loop = 0;
81	u8 saddr_len = 1;
82	u8 *buf_ptr = NULL;
83	u16 saddr = 0;
84	u8 need_gpio = 0;
85
86	if (is_tuner(dev, bus, msg, TUNER_XC5000)) {
87		size = msg->len;
88
89		if (size == 2) {	/* register write sub addr */
90			/* Just writing sub address will cause problem
91			* to XC5000. So ignore the request */
92			return 0;
93		} else if (size == 4) {	/* register write with sub addr */
94			if (msg->len >= 2)
95				saddr = msg->buf[0] << 8 | msg->buf[1];
96			else if (msg->len == 1)
97				saddr = msg->buf[0];
98
99			switch (saddr) {
100			case 0x0000:	/* start tuner calibration mode */
101				need_gpio = 1;
102				/* FW Loading is done */
103				dev->xc_fw_load_done = 1;
104				break;
105			case 0x000D:	/* Set signal source */
106			case 0x0001:	/* Set TV standard - Video */
107			case 0x0002:	/* Set TV standard - Audio */
108			case 0x0003:	/* Set RF Frequency */
109				need_gpio = 1;
110				break;
111			default:
112				if (dev->xc_fw_load_done)
113					need_gpio = 1;
114				break;
115			}
116
117			if (need_gpio) {
118				dprintk1(1,
119				"GPIO WRITE: addr 0x%x, len %d, saddr 0x%x\n",
120				msg->addr, msg->len, saddr);
121
122				return dev->cx231xx_gpio_i2c_write(dev,
123								   msg->addr,
124								   msg->buf,
125								   msg->len);
126			}
127		}
128
129		/* special case for Xc5000 tuner case */
130		saddr_len = 1;
131
132		/* adjust the length to correct length */
133		size -= saddr_len;
134		buf_ptr = (u8 *) (msg->buf + 1);
135
136		do {
137			/* prepare xfer_data struct */
138			req_data.dev_addr = msg->addr;
139			req_data.direction = msg->flags;
140			req_data.saddr_len = saddr_len;
141			req_data.saddr_dat = msg->buf[0];
142			req_data.buf_size = size > 16 ? 16 : size;
143			req_data.p_buffer = (u8 *) (buf_ptr + loop * 16);
144
145			bus->i2c_nostop = (size > 16) ? 1 : 0;
146			bus->i2c_reserve = (loop == 0) ? 0 : 1;
147
148			/* usb send command */
149			status = dev->cx231xx_send_usb_command(bus, &req_data);
150			loop++;
151
152			if (size >= 16)
153				size -= 16;
154			else
155				size = 0;
156
157		} while (size > 0);
158
159		bus->i2c_nostop = 0;
160		bus->i2c_reserve = 0;
161
162	} else {		/* regular case */
163
164		/* prepare xfer_data struct */
165		req_data.dev_addr = msg->addr;
166		req_data.direction = msg->flags;
167		req_data.saddr_len = 0;
168		req_data.saddr_dat = 0;
169		req_data.buf_size = msg->len;
170		req_data.p_buffer = msg->buf;
171
172		/* usb send command */
173		status = dev->cx231xx_send_usb_command(bus, &req_data);
174	}
175
176	return status < 0 ? status : 0;
177}
178
179/*
180 * cx231xx_i2c_recv_bytes()
181 * read a byte from the i2c device
182 */
183static int cx231xx_i2c_recv_bytes(struct i2c_adapter *i2c_adap,
184				  const struct i2c_msg *msg)
185{
186	struct cx231xx_i2c *bus = i2c_adap->algo_data;
187	struct cx231xx *dev = bus->dev;
188	struct cx231xx_i2c_xfer_data req_data;
189	int status = 0;
190	u16 saddr = 0;
191	u8 need_gpio = 0;
192
193	if (is_tuner(dev, bus, msg, TUNER_XC5000)) {
194		if (msg->len == 2)
195			saddr = msg->buf[0] << 8 | msg->buf[1];
196		else if (msg->len == 1)
197			saddr = msg->buf[0];
198
199		if (dev->xc_fw_load_done) {
200
201			switch (saddr) {
202			case 0x0009:	/* BUSY check */
203				dprintk1(1,
204				"GPIO R E A D: Special case BUSY check \n");
205				/*Try read BUSY register, just set it to zero*/
206				msg->buf[0] = 0;
207				if (msg->len == 2)
208					msg->buf[1] = 0;
209				return 0;
210			case 0x0004:	/* read Lock status */
211				need_gpio = 1;
212				break;
213
214			}
215
216			if (need_gpio) {
217				/* this is a special case to handle Xceive tuner
218				clock stretch issue with gpio based I2C */
219
220				dprintk1(1,
221				"GPIO R E A D: addr 0x%x, len %d, saddr 0x%x\n",
222				msg->addr, msg->len,
223				msg->buf[0] << 8 | msg->buf[1]);
224
225				status =
226				    dev->cx231xx_gpio_i2c_write(dev, msg->addr,
227								msg->buf,
228								msg->len);
229				status =
230				    dev->cx231xx_gpio_i2c_read(dev, msg->addr,
231							       msg->buf,
232							       msg->len);
233				return status;
234			}
235		}
236
237		/* prepare xfer_data struct */
238		req_data.dev_addr = msg->addr;
239		req_data.direction = msg->flags;
240		req_data.saddr_len = msg->len;
241		req_data.saddr_dat = msg->buf[0] << 8 | msg->buf[1];
242		req_data.buf_size = msg->len;
243		req_data.p_buffer = msg->buf;
244
245		/* usb send command */
246		status = dev->cx231xx_send_usb_command(bus, &req_data);
247
248	} else {
249
250		/* prepare xfer_data struct */
251		req_data.dev_addr = msg->addr;
252		req_data.direction = msg->flags;
253		req_data.saddr_len = 0;
254		req_data.saddr_dat = 0;
255		req_data.buf_size = msg->len;
256		req_data.p_buffer = msg->buf;
257
258		/* usb send command */
259		status = dev->cx231xx_send_usb_command(bus, &req_data);
260	}
261
262	return status < 0 ? status : 0;
263}
264
265/*
266 * cx231xx_i2c_recv_bytes_with_saddr()
267 * read a byte from the i2c device
268 */
269static int cx231xx_i2c_recv_bytes_with_saddr(struct i2c_adapter *i2c_adap,
270					     const struct i2c_msg *msg1,
271					     const struct i2c_msg *msg2)
272{
273	struct cx231xx_i2c *bus = i2c_adap->algo_data;
274	struct cx231xx *dev = bus->dev;
275	struct cx231xx_i2c_xfer_data req_data;
276	int status = 0;
277	u16 saddr = 0;
278	u8 need_gpio = 0;
279
280	if (msg1->len == 2)
281		saddr = msg1->buf[0] << 8 | msg1->buf[1];
282	else if (msg1->len == 1)
283		saddr = msg1->buf[0];
284
285	if (is_tuner(dev, bus, msg2, TUNER_XC5000)) {
286		if ((msg2->len < 16)) {
287
288			dprintk1(1,
289			"i2c_read: addr 0x%x, len %d, saddr 0x%x, len %d\n",
290			msg2->addr, msg2->len, saddr, msg1->len);
291
292			switch (saddr) {
293			case 0x0008:	/* read FW load status */
294				need_gpio = 1;
295				break;
296			case 0x0004:	/* read Lock status */
297				need_gpio = 1;
298				break;
299			}
300
301			if (need_gpio) {
302				status =
303				    dev->cx231xx_gpio_i2c_write(dev, msg1->addr,
304								msg1->buf,
305								msg1->len);
306				status =
307				    dev->cx231xx_gpio_i2c_read(dev, msg2->addr,
308							       msg2->buf,
309							       msg2->len);
310				return status;
311			}
312		}
313	}
314
315	/* prepare xfer_data struct */
316	req_data.dev_addr = msg2->addr;
317	req_data.direction = msg2->flags;
318	req_data.saddr_len = msg1->len;
319	req_data.saddr_dat = saddr;
320	req_data.buf_size = msg2->len;
321	req_data.p_buffer = msg2->buf;
322
323	/* usb send command */
324	status = dev->cx231xx_send_usb_command(bus, &req_data);
325
326	return status < 0 ? status : 0;
327}
328
329/*
330 * cx231xx_i2c_check_for_device()
331 * check if there is a i2c_device at the supplied address
332 */
333static int cx231xx_i2c_check_for_device(struct i2c_adapter *i2c_adap,
334					const struct i2c_msg *msg)
335{
336	struct cx231xx_i2c *bus = i2c_adap->algo_data;
337	struct cx231xx *dev = bus->dev;
338	struct cx231xx_i2c_xfer_data req_data;
339	int status = 0;
340	u8 buf[1];
341
342	/* prepare xfer_data struct */
343	req_data.dev_addr = msg->addr;
344	req_data.direction = I2C_M_RD;
345	req_data.saddr_len = 0;
346	req_data.saddr_dat = 0;
347	req_data.buf_size = 1;
348	req_data.p_buffer = buf;
349
350	/* usb send command */
351	status = dev->cx231xx_send_usb_command(bus, &req_data);
352
353	return status < 0 ? status : 0;
354}
355
356/*
357 * cx231xx_i2c_xfer()
358 * the main i2c transfer function
359 */
360static int cx231xx_i2c_xfer(struct i2c_adapter *i2c_adap,
361			    struct i2c_msg msgs[], int num)
362{
363	struct cx231xx_i2c *bus = i2c_adap->algo_data;
364	struct cx231xx *dev = bus->dev;
365	int addr, rc, i, byte;
366
367	mutex_lock(&dev->i2c_lock);
368	for (i = 0; i < num; i++) {
369
370		addr = msgs[i].addr;
371
372		dprintk2(2, "%s %s addr=0x%x len=%d:",
373			 (msgs[i].flags & I2C_M_RD) ? "read" : "write",
374			 i == num - 1 ? "stop" : "nonstop", addr, msgs[i].len);
375		if (!msgs[i].len) {
376			/* no len: check only for device presence */
377			rc = cx231xx_i2c_check_for_device(i2c_adap, &msgs[i]);
378			if (rc < 0) {
379				dprintk2(2, " no device\n");
380				mutex_unlock(&dev->i2c_lock);
381				return rc;
382			}
383
384		} else if (msgs[i].flags & I2C_M_RD) {
385			/* read bytes */
386			rc = cx231xx_i2c_recv_bytes(i2c_adap, &msgs[i]);
387			if (i2c_debug >= 2) {
388				for (byte = 0; byte < msgs[i].len; byte++)
389					printk(KERN_CONT " %02x", msgs[i].buf[byte]);
390			}
391		} else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
392			   msgs[i].addr == msgs[i + 1].addr
393			   && (msgs[i].len <= 2) && (bus->nr < 3)) {
394			/* write bytes */
395			if (i2c_debug >= 2) {
396				for (byte = 0; byte < msgs[i].len; byte++)
397					printk(KERN_CONT " %02x", msgs[i].buf[byte]);
398				printk(KERN_CONT "\n");
399			}
400			/* read bytes */
401			dprintk2(2, "plus %s %s addr=0x%x len=%d:",
402				(msgs[i+1].flags & I2C_M_RD) ? "read" : "write",
403				i+1 == num - 1 ? "stop" : "nonstop", addr, msgs[i+1].len);
404			rc = cx231xx_i2c_recv_bytes_with_saddr(i2c_adap,
405							       &msgs[i],
406							       &msgs[i + 1]);
407			if (i2c_debug >= 2) {
408				for (byte = 0; byte < msgs[i+1].len; byte++)
409					printk(KERN_CONT " %02x", msgs[i+1].buf[byte]);
410			}
411			i++;
412		} else {
413			/* write bytes */
414			if (i2c_debug >= 2) {
415				for (byte = 0; byte < msgs[i].len; byte++)
416					printk(KERN_CONT " %02x", msgs[i].buf[byte]);
417			}
418			rc = cx231xx_i2c_send_bytes(i2c_adap, &msgs[i]);
419		}
420		if (rc < 0)
421			goto err;
422		if (i2c_debug >= 2)
423			printk(KERN_CONT "\n");
424	}
425	mutex_unlock(&dev->i2c_lock);
426	return num;
427err:
428	dprintk2(2, " ERROR: %i\n", rc);
429	mutex_unlock(&dev->i2c_lock);
430	return rc;
431}
432
433/* ----------------------------------------------------------- */
434
435/*
436 * functionality()
437 */
438static u32 functionality(struct i2c_adapter *adap)
439{
440	return I2C_FUNC_SMBUS_EMUL | I2C_FUNC_I2C;
441}
442
443static const struct i2c_algorithm cx231xx_algo = {
444	.master_xfer = cx231xx_i2c_xfer,
445	.functionality = functionality,
446};
447
448static const struct i2c_adapter cx231xx_adap_template = {
449	.owner = THIS_MODULE,
450	.name = "cx231xx",
451	.algo = &cx231xx_algo,
452};
453
454/* ----------------------------------------------------------- */
455
456/*
457 * i2c_devs
458 * incomplete list of known devices
459 */
460static const char *i2c_devs[128] = {
461	[0x20 >> 1] = "demod",
462	[0x60 >> 1] = "colibri",
463	[0x88 >> 1] = "hammerhead",
464	[0x8e >> 1] = "CIR",
465	[0x32 >> 1] = "GeminiIII",
466	[0x02 >> 1] = "Aquarius",
467	[0xa0 >> 1] = "eeprom",
468	[0xc0 >> 1] = "tuner",
469	[0xc2 >> 1] = "tuner",
470};
471
472/*
473 * cx231xx_do_i2c_scan()
474 * check i2c address range for devices
475 */
476void cx231xx_do_i2c_scan(struct cx231xx *dev, int i2c_port)
477{
478	unsigned char buf;
479	int i, rc;
480	struct i2c_adapter *adap;
481	struct i2c_msg msg = {
482		.flags = I2C_M_RD,
483		.len = 1,
484		.buf = &buf,
485	};
486
487	if (!i2c_scan)
488		return;
489
490	/* Don't generate I2C errors during scan */
491	dev->i2c_scan_running = true;
492	adap = cx231xx_get_i2c_adap(dev, i2c_port);
493
494	for (i = 0; i < 128; i++) {
495		msg.addr = i;
496		rc = i2c_transfer(adap, &msg, 1);
497
498		if (rc < 0)
499			continue;
500		dev_info(dev->dev,
501			 "i2c scan: found device @ port %d addr 0x%x  [%s]\n",
502			 i2c_port,
503			 i << 1,
504			 i2c_devs[i] ? i2c_devs[i] : "???");
505	}
506
507	dev->i2c_scan_running = false;
508}
509
510/*
511 * cx231xx_i2c_register()
512 * register i2c bus
513 */
514int cx231xx_i2c_register(struct cx231xx_i2c *bus)
515{
516	struct cx231xx *dev = bus->dev;
517
518	if (!dev->cx231xx_send_usb_command)
519		return -EINVAL;
520
521	bus->i2c_adap = cx231xx_adap_template;
522	bus->i2c_adap.dev.parent = dev->dev;
523
524	snprintf(bus->i2c_adap.name, sizeof(bus->i2c_adap.name), "%s-%d", bus->dev->name, bus->nr);
525
526	bus->i2c_adap.algo_data = bus;
527	i2c_set_adapdata(&bus->i2c_adap, &dev->v4l2_dev);
528	bus->i2c_rc = i2c_add_adapter(&bus->i2c_adap);
529
530	if (0 != bus->i2c_rc)
531		dev_warn(dev->dev,
532			 "i2c bus %d register FAILED\n", bus->nr);
533
534	return bus->i2c_rc;
535}
536
537/*
538 * cx231xx_i2c_unregister()
539 * unregister i2c_bus
540 */
541void cx231xx_i2c_unregister(struct cx231xx_i2c *bus)
542{
543	if (!bus->i2c_rc)
544		i2c_del_adapter(&bus->i2c_adap);
545}
546
547/*
548 * cx231xx_i2c_mux_select()
549 * switch i2c master number 1 between port1 and port3
550 */
551static int cx231xx_i2c_mux_select(struct i2c_mux_core *muxc, u32 chan_id)
552{
553	struct cx231xx *dev = i2c_mux_priv(muxc);
554
555	return cx231xx_enable_i2c_port_3(dev, chan_id);
556}
557
558int cx231xx_i2c_mux_create(struct cx231xx *dev)
559{
560	dev->muxc = i2c_mux_alloc(&dev->i2c_bus[1].i2c_adap, dev->dev, 2, 0, 0,
561				  cx231xx_i2c_mux_select, NULL);
562	if (!dev->muxc)
563		return -ENOMEM;
564	dev->muxc->priv = dev;
565	return 0;
566}
567
568int cx231xx_i2c_mux_register(struct cx231xx *dev, int mux_no)
569{
570	return i2c_mux_add_adapter(dev->muxc,
571				   0,
572				   mux_no /* chan_id */,
573				   0 /* class */);
574}
575
576void cx231xx_i2c_mux_unregister(struct cx231xx *dev)
577{
578	i2c_mux_del_adapters(dev->muxc);
579}
580
581struct i2c_adapter *cx231xx_get_i2c_adap(struct cx231xx *dev, int i2c_port)
582{
583	switch (i2c_port) {
584	case I2C_0:
585		return &dev->i2c_bus[0].i2c_adap;
586	case I2C_1:
587		return &dev->i2c_bus[1].i2c_adap;
588	case I2C_2:
589		return &dev->i2c_bus[2].i2c_adap;
590	case I2C_1_MUX_1:
591		return dev->muxc->adapter[0];
592	case I2C_1_MUX_3:
593		return dev->muxc->adapter[1];
594	default:
595		BUG();
596	}
597}
598EXPORT_SYMBOL_GPL(cx231xx_get_i2c_adap);
599